Issued  August  22,  1911. 


630 
UN3I* 

ujo.MVi 

U.  S.  DEPARTMENT  OF  AGRICULTURE. 


FARMERS’  BULLETIN  463. 


THE  SANITARY  PRIVY. 


BY 


C.  W.  STILES, 


Professor  of  Zoology ,  United  States  Public  Health  and  Marine-Hospital  Service , 
and  Consulting  Zoologist ,  Bureau  of  Animal  Industry , 


AND 


L.  L.  LUMSDEN, 

Passed  Assistant  Surgeon ,  United  States  Public  Health  and 
Marine-Hospital  Service. 


WASHINGTON 

GOVERNMENT  PRINTING  OFFICE. 
1911. 


¥1*  ' 


yiO 


United  States  Department  of  Agriculture, 

Office  of  the  Secretary, 

W ashing  ton,  D.  C.,  June  6 ,  1911. 

To  the  farm-ers  of  the  United  States: 

Nothing  is  more  important  to  the  farmer  than  good  health.  Good 
health  can  not  be  preserved  if  the  sanitary  conditions  of  the  farm 
are  bad.  Among  the  worst  conditions  ever  to  be  found  about  any 
home  is  a  soil  that  has  become  polluted  with  excrement  from  the 
human  body.  A  number  of  widely  prevalent  diseases  have  been 
spread  by  means  of  such  polluted  soil,  simply  because  the  facts  have 
not  been  generally  known.  This  bulletin  treats  of  such  soil  pollu¬ 
tion  and  certain  simple  plans  for  avoiding  it. 

Having  at  heart  the  best  interests  of  the  American  farmer  and  his 
family,  I  consider  it  my  personal  duty  to  appeal  to  eve^y  American 
farmer  to  weigh  well  the  facts  here  presented,  to  do  all  in  his  power 
to  remove  any  insanitary  conditions  that  he  may  find  on  his  farm  or 
in  his  neighborhood,  and  thus,  by  protecting  the  members  of  his 
family,  perform  one  of  his  highest  patriotic  duties. 

James  AT  ILSON, 
Secretary  of  Agriculture. 

463 


3 


LETTER  OF  TRANSMITTAL. 


United  States  Treasury  Department, 

Public  Health  and  Marine -Hospital  Service, 

Was  king  tan,  D.  G .,  April  20,  1911. 

Sir  :  With  the  approval  of  the  Secretary  of  the  Treasury,  I  have 
the  honor  to  transmit  herewith  a  manuscript  entitled  “  The  Sanitary 
Privy,”  prepared  by  C.  W.  Stiles  and  L.  L.  Lumsden,  of  the  Hygienic 
Laboratory  of  this  service.  Professor  Stiles  is  also  consulting  zoolo¬ 
gist  in  the  Bureau  of  Animal  Industry,  Department  of  Agriculture. 
For  some  years  past  these  two  officers  have  been  making  a  special 
study  of  certain  diseases  which  are  particularly  incident  to  farm  life 
and  of  the  methods  by  which  these  infections  are  spread,  and  their 
reports  thereon  have  appeared  in  the  publications  of  the  Public 
Health  and  Marine-Hospital  Service.  These  have  been  revised,  and 
the  manuscript,  with  the  description  of  additional  research  work,  is 
submitted,  that  it  may  become  available  through  the  Department  of 
Agriculture  to  those  living  on  farms,  who  naturally  look  to  your 
department  for  such  information. 

Respectfully,  Walter  Wyman, 

Surgeon  General. 

Hon.  James  Wilson, 

Secretary  of  Agriculture . 

463 

4 


CONTENTS. 


Page. 

Soil  pollution .  7 

Diseases  spread  from  man  by  soil  pollution .  8 

Diseases  spread  from  man  to  man .  8 

Bacterial  diseases .  8 

Typhoid  fever .  8 

Dysentery  and  diarrhea  (“summer  complaint”) .  10 

Tuberculosis .  10 

Parasitic  diseases .  10 

Hookworm  disease .  11 

Cochin-China  diarrhea .  11 

Eelworm  infection .  11 

Amoebic  dysentery . .  11 

Parasitic  diseases  spread  from  man  to  live  stock  and  then  back  to  man. ...  12 

Beef-measle  tapeworm .  12 

Pork-measle  tapeworm .  12 

Human  excrement  as  a  breeding  place  for  flies .  12 

Privy  conditions  on  some  American  farms .  13 

Different  kinds  of  privies .  13 

The  popular  idea  of  the  purpose  of  a  privy .  13 

The  essential  parts  of  a  privy .  13 

The  essential  problems  in  constructing  a  privy .  13 

The  kinds  of  privies  that  are  not  sanitary .  14 

The  kinds  of  privies  that  are  sanitary . ( . ; .  15 

The  “dry  system ” .  15 

The  “wet  system” . ’ .  16 

The  L.  R.  S.  privy .  17 

Practical  working  of  the  apparatus .  18 

Directions  for  building  a  sanitary  privy .  21 

A  single-seated  privy .  25 

Framework .  25 

Sides .  25 

Back . ' .  25 

Floor .  26 

Front .  26 

Roof .  27 

Box .  27 

Back  trapdoor . • .  27 

Frontdoor . 27 

Ventilators .  28 

Lath .  28 

Receptacle .  28 

Order  for  material .  29 

Estimate  of  material  for  school  or  church  privy .  29 

How  to  keep  a  privy  sanitary .  30 

Wrong  ways  of  disposing  of  night  soil .  30 

The  right  way  to  dispose  of  night  soil .  30 

The  privy  at  the  country  school  and  church .  32 

Civic  responsibility  in  respect  to  privies .  32 


463 


5 


ILLUSTRATIONS. 


Page. 

Fig.  1.  A  fly  with  germs  (greatly  magnified)  on  its  legs .  9 

2.  An  insanitary  privy,  open  in  back .  14 

3.  Improved  L.  It.  S.  privy .  17 

4.  Inside  view  of  L.  It.  S.  privy .  18 

5.  Rear  view  of  L.  R.  S.  privy .  19 

6.  A  single-seated  sanitary  privy .  22 

7.  Rear  and  side  view  of  a  single-seated  sanitary  privy .  23 

8.  The  scantling  necessary  for  the  framework  of  a  single-seated  sanitary 

privy . . .  24 

9.  The  framework  (assembled)  for  a  single-seated  sanitary  privy .  26 

463 

6 


THE  SANITARY  PRIVY. 


SOIL  POLLUTION. 

It  is  common  knowledge  among  intelligent  farmers  that  in  many 
instances  when  live  stock,  suchr  as  horses,  cattle,  sheep,  or  hogs,  are 
pastured  year  after  year  m  the  same  field,  the  animals  do  not  thrive; 
in  fact,  that,  sooner  or  later,  many  sicken  and  die;  this  is  especially 
true  of  the  young  animals. 

4  _ 

The  explanation  of  this  fact  is  clear.  Animals  harbor  parasitic 
worms  and  germs  in  their  intestines;  the  worms  lay  eggs,  which  are 
passed  in  the  droppings;  the  eggs  develop  into  young  worms,  which 
in  turn  reinfect  the  live  stock.  If  a  pasture  is  in  constant  use  the 
ground  becomes  heavily  infested  with  young  worms  and  other  germs ; 
the  smaller  the  pasture  in  proportion  to  the  number  of  animals  kept 
in  it,  the  more  intensified  the  soil  pollution  becomes.  Warmth  and 
moisture  are  especially  favorable  to  the  hatching  out  of  worms  from 
the  eggs  passed  in  the  droppings,  hence,  during  warm,  moist  seasons, 
or  in  warm,  moist  localities,  the  infection  of  the  stock  is  likely  to  be 
more  severe.  The  more  heavily  the  animals  are  infected  with  para¬ 
sites,  the  less  they  thrive;  their  digestion  is  weakened  and  their 
blood  becomes  watery,  so  that  a  considerable  proportion  of  the  food 
given  them  is  wasted  in  that  it  does  not  go  to  make  meat;  their 
growth  is  retarded  and  their  fertility  is  lessened;  and  finally  infec¬ 
tion  reaches  such  a  degree  that  many  of  the  animals  can  no  longer 
withstand  it,  and  they  sicken  and  die.  Thus,  the  soil  pollution  of  a 
field  by  the  live  stock  eventually  renders  the  pastures  unfavorable 
for  raising  animals.  The  practical  farmer,  having  observed  this  fact, 
moves  his  stock  to  other  ground  in  order  “  to  give  the  old  pasture  a 
rest ;  ”  by  so  doing  he  removes  his  animals  from  exposure  to  infec¬ 
tion,  allowing  the  infectious  germs  and  young  worms  in  the  old 
pasture  to  die  out. 

The  foregoing  facts  regarding  the  effects  of  soil  pollution  upon 
the  health  of  animals,  such  as  horses,  sheep,  cattle,  swine,  and  chick¬ 
ens,  apply  with  equal  force  to  human  beings,  because  human  beings 
also  harbor  parasitic  worms  and  germs,  which  are  discharged  in  the 
excreta,  pollute  the  soil,  are  again  conveyed  to  people,  and  thus  con¬ 
tinue  the  round  of  infection  at  an  increasing  rate.  Soil  pollution  by 

Note. — A  list  giving  the  titles  of  all  Farmers’  Bulletins  available  for  distri¬ 
bution  will  be  sent  free  upon  application  to  a  Member  of  Congress  or  the  Secre¬ 
tary  of  Agriculture. 


8 


SANITARY  PRIVY. 


human  excreta  endangers  the  health  of  a  family,  just  as  soil  pollu¬ 
tion  of  a  pasture  by  the  droppings  of  animals  endangers  the  live 
stock. 

In  order  to  prevent  the  evil  effects  of  soil  pollution  from  extending 
to  his  live  stock,  the  farmer  must  resort  to  more  or  less  expensive 
methods,  such  as  purchase  of  additional  pasture  lands  or  burning 
the  pasture.  But  since  human  beings,  on  account  of  their  superior 
intelligence,  can  be  taught  to  frequent  an  appointed  place  to  deposit 
their  excreta,  it  is  possible  (by  the  expenditure  of  a  few  dollars  for 
a  sanitary  privy)  to  prevent  soil  pollution  with  human  excreta, 
thereby  protecting  the  family,  and  enabling  it  to  live  year  after  year 
on  the  same  premises  (family  pasture)  without  danger,  at  the  same 
time  saving  doctors'  bills  and  avoiding  unnecessary  sickness  and 
death. 


DISEASES  SPREAD  FROM  MAN  BY  SOIL  POLLUTION. 

It  is  especially  the  diseases  caused  by  parasites  (both  animal  and 
bacterial)  of  the  intestine,  lungs,  liver,  kidneys,  and  bladder  that  are 
spread  by  soil  pollution.  Some  of  these  diseases  are  spread  from 
human  being  to  human  being;  others  are  spread  from  human  beings 
to  the  farm  animals.  Therefore,  in  preventing  soil  pollution  by  per¬ 
sons,  both  families  and  live  stock  are  protected. 

The  proper  disposal  of  human  excreta  is  recognized  by  sanitarians 
as  the  most  important  measure  needed  to  prevent  the  spread  of 
typhoid  fever,  hookworm  disease,  the  dysenteries,  and  certain  other 
widely  prevalent  diseases. 

DISEASES  SPREAD  FROM  MAN  TO  MAN. 

Some  of  the  diseases  which  come  under  this  heading  are  caused  by 
microscopic  parasites  known  as  bacteria  ;  others  by  animal  parasites, 
which  are  considerably  larger  than  the  bacteria. 

BACTERIAL  DISEASES. 

Among  the  most  important  diseases  under  this  heading  may  be 
mentioned  typhoid  fever,  dysentery  and  diarrhea  (“  summer  com¬ 
plaint”),  and  tuberculosis  (“consumption").  - 

Typhoid  fever. — Every  person  who  contracts  typhoid  fever  does  so 
because  he  has  recently  swallowed  some  typhoid  germs  that  have  been 
passed  in  the  stools  or  urine  of  some  other  person,  who  either  (as  a 
patient)  was  suffering  from  typhoid  or  (as  a  “  carrier  ”)  was  carrying 
the  germs  without  showing  symptoms. 

The  germs  (bacilli)  of  typhoid  fever  are  of  very  minute  size,  a 
single  germ  (bacillus)  being  only  about  Tgfoi>  of  an  inch  in  length 

463 


SANITARY  PRIVY. 


9 


and  only  about  3^0-0  of  an  inch  in  thickness.  Like  molds  and 
yeasts,  they  are  plants,  and  under  favorable  conditions  (as  in  milk, 
for  instance)  they  multiply  at  a  very  rapid  rate,  so  that  in  a  few 
hours  a  single  germ  may  increase  to  thousands.  Thousands  of  these 
little  germs  may  be  contained  in  a  particle  of  feces  no  larger  than 
the  head  of  an  ordinary  pin,  or  in  a  small  drop  of  urine,  and  hundreds 
may  be  carried  on  the  leg  of  a  fly  (fig.  1).  A  person  suffering  from 
typhoid  fever  discharges  myriads  of  these  germs  in  the  stools  and 
urine.  Therefore,  the  excreta  from  typhoid  patients  should  be  re¬ 
garded  as  highly  poisonous,  and  everything  which  may  become  soiled 
with  the  smallest  quantity  of  feces  or  urine  should  be  thoroughly 
disinfected  by  heat-  or  chemicals. 

After  being  discharged  in  the  excreta  from  the  bodies  of  persons, 
typhoid  germs  gradually  die  out,  but  the  length  of  time  during  which 
they  will  survive  in  the  excreta  is  affected  by  a  number  of  conditions; 
in  some  instances  they  have  been  found  to  live  for  over  a  year  in 
the  contents  of  privies  and  privy  vaults  and  in  excreta  mixed  with 
earth.  Therefore,  excreta  which  have  been  passed  through  a  septic 
tank  or  which  have  been  stored  for 
months  in  a  privy  or  privy  vault 
should  not  be  regarded  as  being 
free  from  typhoid  germs. 

Persons  in  the  early  stages  of 
typhoid  fever,  before  becoming  ill 
enough  to  take  to  bed  (and  some 
time  perhaps  before  the  physician 
is  called  in),  may  discharge  typhoid  germs  in  their  excreta.  Some 
persons  contract  infection  and  though  having  symptoms  of  the  dis¬ 
ease  in  a  mild  form  (“  walking  cases  of  typhoid  fever  ”)  never  be¬ 
come  ill  enough  to  give  up  and  take  to  bed.  Other  persons  contract 
and  harbor  the  infection  for  a  few  days  or  weeks  without  showing 
any  symptoms  whatever  (“temporary  typhoid-bacillus  carriers'5). 
In  many  instances  the  excreta  from  such  persons  are  as  heavily 
charged  with  typhoid  germs  as  are  those  from  persons  suffering 
with  the  severest  attacks  of  the  disease.  Some  persons  recovered 
from  attacks  of  the  disease  continue  to  discharge  typhoid  germs  in 
their  stools  or  urine,  or  both,  for  weeks,  months,  or  even  years 
(“chronic  typhoid-bacillus  carriers”).  In  view  of  all  these  now 
thoroughly  established  facts,  it  is  evident  that  to  prevent  the  spread 
of  typhoid  infection  from  persons  it  is  necessary  to  dispose  properly 
of  the  excreta  from  all  persons  at  all  times.  This  can  be  done  by 
the  use  of  sanitary  privies. 

If  the  excreta  are  not  properly  disposed  of  it  is  readily  under¬ 
stood  that  the  germs  may  be  carried  in  a  number  of  ways  to  the 
100830°— Bull  463—11 - 2 


Fig.  1. — A  fly  with  germs  (greatly  mag¬ 
nified)  on  its  legs. 


10 


SANITARY  PRIVY. 


water  or  food  supplies,  and  then  be  swallowed  by  and  cause  infec¬ 
tion  in  persons.  They  may  be  carried  by  drainage  or  seepage  or 
tracked  on  the  feet  of  persons,  live  stock,  and  poultry  to  the  well 
or  spring.  They  may  be  carried  directly  by  flies  from  the  excreta 
to  the  foods  in  the  kitchen  or  dining  room.  If  spread  about  the 
place  they  will  from  time  to  time  get  on  the  hands  of  persons,  and 
thence  into  the  water  or  foods. 

Some  of  the  ways  in  which  typhoid  germs  in  the  excreta  from 
infected  persons  may  be  conveyed  to  other  persons  are  shown  in  the 
following  diagram : 

Diagram  of  modes  of  spread  of  typhoid  fever. 


Excreta  from 


Typhoid' 
patients  or 
Typhoid 

[Fingers . 
Flies  . . . . 

•  to  . 

Water _ 

germ 

carriers 

Foods  . 

Milk . . 

Raw  vegetables  and 

fruits . . 

Bread,  cake,  candy, 
etc . . 


>  to 


JMouths  of 
1  persons 


The  foregoing  diagram  shows  that  the  easiest  way  of  protecting 
against  typhoid  fever  is  to  dispose  of  the  excreta  in  such  a  manner 
that  the  germs  contained  therein  can  not  be  spread.  This  can  be 
done  by  using  sanitary  privies. 

Dysentery  and  diarrhea  (“summer  complaint”). — Dysentery  and 
similar  infections  can  be  prevented  in  the  same  way  as  typhoid  fever, 
as  their  method  of  spread  is  the  same. 

Tuberculosis. — Although  the  danger  of  spreading  tuberculosis  by 
spitting  must  be  constantly  held  in  mind,  it  is  important  to  remem¬ 
ber  also  that  many  tubercle  bacilli  may  be  discharged  in  the  feces, 
because  persons  with  lung  tuberculosis  (“  consumption  ”)  frequently 
swallow  their  sputum,  and  also  because  some  persons  have  tubercu¬ 
losis  of  the  bowels.  The  spread  of  tuberculosis  by  soil  pollution  may 
be  prevented  by  using  sanitary  privies. 

PARASITIC  DISEASES. 

Among  the  diseases  caused  by  animal  parasites,  and  spread  by  soil 
pollution  from  man  to  man,  there  may  be  mentioned,  especially,  hook¬ 
worm  disease,  Cochin-China  diarrhea,  eelworm  infection,  pinworm 
infection,  blood-fluke  infection,  amoebic  dysentery,  and  many  other 
diseases.  In  some  of  these  maladies  the  infection  is  spread  in  much 
the  same  way  as  is  that  of  typhoid  fever,  the  germs  being  swallowed ; 
in  others  the  infection  may  take  place  through  the  skin.  All  of  these 
diseases  can  be  prevented  by  using  sanitary  privies. 

463 


SANITARY  PRIVY. 


11 


Hookworm  disease. — There  are  in  this  country  at  least  2,000,000 
cases  of  hookworm  disease.  The  parasites,  which  are  about  half  an 
inch  long,  attach  themselves  to  the  wall  of  the  bowels,  which  they 
wound,  and  from  which  they  suck  blood. 

The  worms  lay  eggs  which  are  passed  in  the  stools  and  which 
escape  from  the  body  in  no  other  way.  If  the  ground  is  polluted  by 
the  human  excreta,  this  disease  spreads,  but  if  the  excreta  are  depos¬ 
ited  in  a  sanitary  privy,  and  properly  disposed  of,  the  disease  can  be 
easily  prevented. 

Under  favorable  conditions,  from  these  eggs,  which  are  too  small  to 
be  seen  with  the  naked  eye,  hatch  out  within  a  few  hours  tiny  worms ; 
these  worms  grow  and  shed  their  skin,  much  like  a  snake ;  when  about 
one  to  two  wTeeks  old,  but  still  only  about  one- fortieth  of  an  inch 
long  and  therefore  scarcely  visible  to  the  naked  eye,  they  may  be 
swallowed,  or  they  may  burrow  through  the  skin,  especially  of  bare¬ 
footed  children,  and  cause  that  condition  known  as  “ground  itch,'’ 
66  dew  itch,”  “  dew  sores,”  “  toe  itch,”  etc.  Wherever  “  ground  itch  ” 
exists,  it  is  proof  that  somewhere  in  that  locality  soil  pollution  has 
occurred,  because  there  is  a  privy  which  is  either  not  properly  built, 
or  not  properly  taken  care  of,  or  not  properly  used,  or  because  there 
is  no  privy  at  all. 

From  the  skin  these  tiny  worms  get  into  the  blood  and  gradually 
make  their  way  to  the  bowels,  where  they  grow  to  adult  worms,  and 
in  their  turn  lay  eggs. 

If  any  member  of  the  family  or  any  person  on  the  farm  is  pale, 
weak,  or  sickly,  and  has  had  “  ground  itch  ”  within  10  years  past,  the 
family  physician  should  be  consulted  as  to  whether  the  trouble  is 
due  to  hookworms.  In  many  of  the  States  the  State  board  of  health 
will  either  make  or  have  made  a  microscopic  examination,  free  of 
charge,  to  determine  the  point  definitely. 

Although  hookworm  disease  may  have  serious  effects,  even  result¬ 
ing  in  death,  it  can  be  easily  cured  at  a  slight  expense,  and  it  can  be 
entirely  eradicated  if  sanitary  privies  are  built  and  used. 

Cochin-China  diarrhea. — This  is  a  disease  which  is  spread  very  much 
in  the  same  way  as  hookworm  disease.  It  is  very  difficult  to  treat 
successfully,  but  it  can  be  absolutely  prevented  by  the  use  of  sanitary 
privies. 

Eelworm  infection. — The  eelworms  are  about  as  large  as  a  lead 
pencil,  and  are  found  among  children.  Whenever  found  they  prove 
that  there  is  something  wrong  with  the  sanitary  conditions. 

Amoebic  dysentery. — This  is  a  very  serious  disease.  It  may  cause 
death,  but  its  spread  can  be  prevented  by  the  use  of  sanitary 
privies. 

463 


12 


SANITARY  PRIVY. 


PARASITIC  DISEASES  SPREAD  EROM  MAN  TO  LIVE  STOCK  AND 

THEN  BACK  TO  MAN. 

At  least  two  kinds  of  tapeworms  are  spread  from  man  to  live  stock 
and  back  to  man  because  of  lack  of  sanitary  privies. 

Beef-measle  tapeworm. — This  tapeworm,  when  harbored  in  the  in¬ 
testine  of  man,  lays  thousands  of  eggs,  which  are  discharged  in  the 
stools,  and  if  scattered  about  may  be  swallowed  bv  cattle.  Here  thev 
cause  “beef  measles."  reducing  the  value  of  the  beef.  By  eating 
measly  beef  man  may  become  infected  with  this  tapeworm. 

Pork-measle  tapeworm. — The  eggs  of  this  tapeworm  are  passed  in 
the  stools  of  man  and  swallowed  by  swine,  in  which  they  cause 
“  pork  measles."  By  eating  such  pork  man  may  become  infected 
with  tapeworms.  This  tapeworm  is  especially  dangerous,  because 
if  a  person  harbors  it  and  pollutes  the  soil  with  his  excreta  containing 
the  eggs,  these  eggs  may  be  swallowed  by  persons  and  cause  a  serious 
disease  known  as  “  pork  measles "  in  man,  which  may  cause  blind¬ 
ness,  insanity,  and  death. 

Both  of  these  tapeworm  infections  can  be  prevented  b}7  the  use 
of  sanitary  privies. 

HUMAN  EXCREMENT  AS  A  BREEDING  PLACE  EOR  FLIES. 

Flies  and  many  other  insects  feed  upon  and  breed  in  filth,  such 
as  manure  and  human  excrement.  Whenever  a  fly  is  seen  it  is  posi¬ 
tive  proof  of  the  existence  of  some  filth  in  the  neighborhood.  It  is 
much  more  filthy  and  much  more  dangerous  to  have  flies  in  the 
kitchen  and  dining  room  than  to  have  bedbugs  in  the  bedroom. 

Flies  can  carry  various  disease  germs  to  man.  By  so  doing  they 
kill  thousands  of  people,  especially  babies,  every  year;  therefore  kill 
the  flies  and  save  the  babies. 

If  flies  have  access  to  human  excrement,  they  not  only  feed  upon  it, 
but  they  lay  their  eggs  in  it.  After  a  few  hours  the  egg  hatches  out 
a  maggot;  this  feeds  in  the  filth  for  several  (about  five)  days  and 
then  forms  a  pupa :  after  about  five  days  the  adult  fly  comes  out  of 
the  pupal  case,  feeds  on  the  filth,  and  carries  disease  germs  from  the 
filth  to  the  house,  depositing  these  germs  on  the  foods.  Thus  flies 
carry  disease  to  people.  A  fly  drops  his  excrement  about  once  every 
44  minutes  and  may  spread  germs  not  only  in  this  way,  but  also  with 
his  feet,  wings,  and  mouth  parts. 

Even  if  excrement  containing  fly  maggots  is  buried  under  as  much 
as  6  feet  of  sand,  the  maggots  can  crawl  to  the  surface,  bringing 
disease  germs  with  them. 

Thus  it  is  clear  that  if  flies  are  kept  away  from  human  excrement, 
not  only  will  they  decrease  in  numbers,  but  they  will  be  prevented 
from  spreading  certain  diseases,  such  as  typhoid  fever.  This  can 
be  done  by  the  use  of  sanitary  privies. 

463 


SANITARY  PRIVY. 


13 


PRIVY  CONDITIONS  ON  SOME  AMERICAN  FARMS. 

The  privy  on  the  American  farm  possibly  has  not  received  the  at¬ 
tention  that  its  importance  deserves.  Some  American  farms  have  no 
privy  at  all.  This  means  that  some  farm  families  are  being  need¬ 
lessly  exposed  to  sickness  and  death.  It  means  that  these  families  are 
following  a  custom  which  not  only  needlessly  increases  sickness  and 
death,  but  which  decreases  the  value  and  productiveness  of  their 
farms.  The  warmer,  more  moist,  and  more  shaded  the  locality,  the 
greater  is  the  danger  resulting  from  lack  of  sanitary  privies. 

City  health  authorities  are  gradually  awakening  to  the  dangers 
connected  with  the  supplies  of  milk,  fresh  vegetables,  and  fresh  fruits 
from  insanitary  farms;  hence  not  only  from  the  standpoint  of  pre¬ 
serving  the  health  of  persons  living  on  farms  and  increasing  the  pro¬ 
ductiveness  of  the  farms,  but  also  from  the  standpoint  of  marketing 
farm  produce,  it  is  important  for  farms  to  be  provided  with  sanitary 
privies. 

DIFFERENT  KINDS  OF  PRIVIES. 

The  popular  idea  of  the  purpose  of  a  privy. — To  the  popular  mind  a 
privy  (as  indicated  by  its  name)  is  a  structure  to  which  a  person 
may  retire  in  private  when  responding  to  the  daily  calls ‘of  nature. 
In  the  minds  of  most  persons  modesty  and  privacy  are  the  chief  con¬ 
siderations  which  lead  to  the  construction  of  a  privy.  As  such 
privacy  may  be  secured  by  a  clump  of  bushes  or  a  grove  of  trees, 
some  persons  consider  a  privy  unnecessary. 

Modesty  and  privacy  are  laudable  objects,  but  all  must  agree  that 
they  are  of  infinitely  less  importance  than  the  great  object  of  saving 
human  life  by  preventing  the  spread  of  disease. 

The  essential  parts  of  a  privy. — A  privy  should  consist  of  two  chief 
parts,  namely:  First,  a  receptacle  for  the  excreta;  secondly,  a  room 
to  insure  privacy. 

The  essential  problems  in  constructing  a  privy. — From  the  foregoing 
it  is  clear  that  the  two  great  problems  to  be  held  in  mind  in  con¬ 
structing  a  privy  are:  First,  to  protect  the  receptacle  for  the  excreta 
in  such  a  way  that  the  germs  can  not  be  spread;  secondly,  to  con¬ 
struct  the  entire  outhouse  in  such  a  way  that  persons  will  seek  to 
use  it  and  not  to  avoid  it — in  other  words,  not  only  must  it  insure 
privacy,  but  it  must  not  be  a  disagreeable  place  in  which  to  be  pri¬ 
vate.  This  latter  point  is  especially  important  in  warm  climates, 
for  many  a  privy  is  so  disagreeable  in  warm  weather  that  people, 
especially  men,  very  frequently  avoid  it.  Still  another  point  must  be 
considered,  namelv,  the  cost  of  construction  and  maintenance  must 
be  brought  within  the  purse  limits  of  the  poor  as  well  as  of  the  well- 
to-do  family. 


463 


14 


SANITARY  PRIVY. 


The  kinds  of  privies  that  are  not  sanitary. — If  the  excreta  are  scat¬ 
tered  broadcast,  the  infection  they  contain  is  also  scattered  far  and 
wide.  If  the  excreta  are  deposited  in  one  place,  the  infection  they 
contain  is  more  restricted.  Therefore,  any  kind  of  privy  is  better 
than  none.  From  a  faulty  privy,  however,  much  infection  may  be 
spread  in  various  ways,  as,  for  instance,  by  drainage  and  seepage, 
or  by  chickens,  swine,  and  dogs,  or  by  the  feet  of  persons,  or  by 
insects,  especially  flies. 


Fig.  2. — An  insanitary  privy,  open  in  back.  (Stiles,  1910.) 


Figure  2  represents  a  dangerous  type  of  privy.  On  a  systematic 
rating  it  should  not  be  marked  higher  than  10  on  a  scale  of  100,  there¬ 
fore  it  is  90  per  cent  below  perfect.  The  protection  afforded  by  this 
privy  depends  in  great  measure  upon  the  frequency  with  which  the 
excrement  is  removed.  But  even  if  this  privy  is  cleaned  every  day, 
chickens,  hogs,  and  flies  have  access  to  the  fresh  night  soil  for  a 
463 


SANITARY  PRIVY. 


15 


number  of  hours,  and,  besides  that,  the  ground  under  and  around  the 
outhouse  becomes  polluted. 

Even  if  such  a  privy  is  provided  in  the  back  with  a  tightly  fit¬ 
ting  trapdoor,  so  as  to  exclude  domesticated  animals  and  to  prevent 
the  toilet  paper  from  being  blown  about,  its  efficiency  is  increased  by 
only  about  15  points,  so  that  it  should  not  be  ranked  more  than  25  on 
a  scale  of  100.  Insects,  such  as  flies,  ants,  and  roaches,  still  have 
access  to  the  night  soil,  which  also  pollutes  the  ground  under  and 
around  the  privy. 

The  kinds  of  privies  that  are  sanitary. — A  sanitary  privy  must  meet 
the  following  requirements: 

(1)  The  excreta  must  not  touch  the  ground;  hence  some  kind  of 
water-tight  receptacle  (box,  pail,  tub,  barrel,  tank,  or  vault)  for  the 
excreta  must  be  used  under  the  seat. 

(2)  Domesticated  animals  must  not  have  access  to  the  night  soil; 
therefore  the  privy  should  have  a  trapdoor  in  the  back  to  exclude 
them. 

(3)  Flies  and  other  insects  must  not  have  access  to  the  excreta; 
therefore  the  entire  privy  must  be  made  rigidly  flyproof,  or  some 
substance  must  be  used  in  the  receptacle  to  protect  the  contents  from 
insects. 

Two  types  of  sanitary  privies  are  generally  recognized,  namely, 
the  so-called  “  dry  system  ”  and  the  so-called  “  wet  system.” 

THE  “  DRY  SYSTEM.” 

In  the  “  dry-system  ”  privies  dry  earth,  road  dust,  wood  ashes,  or 
lime  is  kept  in  the  privy,  and  is  scattered  on  the  excreta  every  time 
the  privy  is  used. 

The  dry  system,  if  properly  managed,  presents  the  following 
advantages : 

(1)  It  decreases  the  offensiveness  of  the  privy  contents. 

(2)  It  is  cheap. 

(3)  It  decreases  the  chance  of  spread  of  infection  by  insects. 

(4)  It  is  an  easy  system  to  manage. 

The  disadvantages  of  the  dry  system  are  the  following: 

(1)  It  is  very  difficult  to  make  a  dry  privy  rigidly  fly  proof,  hence 
flies  usuallv  do  have  more  or  less  access  to  the  excreta,  on  which 
they  feed  and  on  which  they  lay  their  eggs. 

(2)  Its  efficiency  depends  upon  the  careful  and  faithful  coopera¬ 
tion  of  all  persons  (including  children)  who  use  the  privy,  and 
experience  shows  that  such  cooperation  can  not  be  relied  upon. 

(3)  It  increases  the  amount  of  material  to  be  removed;  hence  it 
increases  the  labor  and  frequency  of  necessary  cleaning. 

463 


16 


SANITARY  PRIVY. 


(4)  Experience  shows  that  it  is  exceptional  that  the  excrement  is 
properly  covered  with  dry  earth  or  lime;  hence  the  system  is  not 
so  efficient  as  is  popularly  supposed. 

(5)  Neither  dry  earth  nor  lime,  in  practical  usage,  can  be  relied 
upon  to  destroy  all  disease  germs  which  may  be  in  the  excreta ;  hence 
their  use  is  likely  to  give  rise  to  a  false  sense  of  security  in  the  public 
mind. 

(6)  If  the  dejecta  at  the  time  of  burial  contain  fly  grubs  these 
larvae  may  crawl  through  the  earth  to  the  surface,  where  they  can 
complete  their  development  into  adult  flies  and  spread  infection 
from  the  buried  night  soil. 

Privies  of  the  “  dry  system  ”  should  not  be  marked  more  than 
75  points  on  a  scale  of  100. 

Figures  6  and  7  (pages  22  and  23)  represent  an  outhouse  which 
may  be  used  as  a  dry  privy. 

THE  WET  SYSTEM.” 

In  the  “  wet-system  ”  privies  some  fluid  is  used  in  the  receptacle 
either  (1)  to  disinfect  the  excreta,  or  (2)  to  act  as  an  insect  repel¬ 
lent,  or  (3)  to  increase  the  destruction  of  disease  germs  in  the  ex¬ 
creta  by  natural  fermentation.  Figures  6  and  7  represent  outhouses 
which  can  be  used  as  “  wet-system  ”  privies. 

The  advantages  of  the  “  wet  system,”  when  applied  to  outhouses 
shown  in  figures  6  and  7,  are : 

(1)  It  decreases  the  offensiveness  of  the  privy  contents. 

(2)  It  is  cheap. 

(3)  It  greatly  decreases  the  chances  of  spread  of  infection  by 
flies  because. they  can  not  breed  in  the  excreta;  hence  rigid  fly  screen- 
ing  is  not  so  necessary. 

(4)  It  kills  or  renders  harmless  a  considerable  proportion  of  cer¬ 
tain  infections  contained  in  the  excreta. 

(5)  Its  efficiency  does  not  depend  upon  the  intelligence  or  coopera¬ 
tion  of  all  persons  using  it. 

The  disadvantages  of  the  “  wet  system,”  as  applied  to  outhouses 
shown  in  figures  6  and  7,  are: 

(1)  It  is  more  difficult  to  keep  clean  than  the  “dry  system,”  be¬ 
cause  of  the  danger  of  soiling  the  floor  when  the  receptacle  is  emptied. 

(2)  Unless  the  receptacle  is  very  deep  there  is  likely  to  be  more  or 
less  splashing. 

(3)  The  labor  and  frequency  of  cleaning  are  about  the  same  as  in 
the  case  of  the  “  dry  system.” 

If  the  wet  system  is  used  it  is  best  to  fill  the  receptacle  about  one- 
fourth  full  of  water,  on  the  surface  of  which  a  cup  of  petroleum 
is  poured.  The  petroleum  acts  as  an  insect  repellent. 

463 


SANITARY  PRIVY. 


17 


Two  sets  of  receptacles  should  be  provided.  While  one  set  is  be¬ 
ing*  used  under  the  seat,  the  other  set  is  covered  and  permitted  to 
stand  so  as  to  lengthen  the  period  of  fermentation. 

THE  L.  It.  S.  PRIVY.1 

On  account  of  the  various  objections  raised  against  the  different 
styles  of  privies  now  in  use,  an  effort  has  been  made  to  construct  a 
device  which  will  decrease  the  disadvantages  and  at  the  same  time 
increase  the  advantages  connected  with  the  older  types  of  outhouses. 
The  results  ob¬ 
tained  from  various 
experiments  have 
been  applied  to  an 
apparatus  known  as 
the  L.  R.  S.  privy 
(figs.  3,  4,  and  5). 

This  apparatus 
consists  of  the  fol¬ 
lowing  parts : 

(1)  A  water-tight 
barrel  or  other  con¬ 
tainer  to  receive  and 
liquefy  the  excreta. 

(2)  A  covered 
water-tight  barrel, 
can,  or  other  vessel 
to  receive  the  efflu¬ 
ent  or  outflow. 

(3)  A  connecting 
pipe  about  2f  inches 
in  diameter,  about 
12  inches  long,  and 
provided  with  an  open  T  at  one  end,  both  openings  of  the  T  being 
covered  with  wire  screens. 

(4)  A  tight  box,  preferably  zinc  lined,  which  fits  tightly  on  the  fop 
of  the  liquefying  barrel.  It  is  provided  with  an  opening  on  top  for 
the  seat,  which  has  an  automatically  closing  lid. 

(5)  An  antisplashing  device  consisting  of  a  small  board  placed 
horizontally  under  the  seat  about  an  inch  below  the  level  of  the 
transverse  connecting  pipe;  it  is  held  in  place  by  a  rod,  which  passes 
through  eyes  or  rings  fastened  to  the  box,  and  by  which  the  board  is 

1  Lumsden,  Roberts,  and  Stiles :  Preliminary  note  on  a  simple  and  inexpensive  ap¬ 
paratus  for  use  in  safe  disposal  of  night  soil.  Public  Health  Reports,  1910,  Nov.  11, 
v.  25  (45),  pp.  1619—1623,  fig.  1. 


18 


SANITARY  PRIVY. 


raised  and  lowered.  The  liquefying  tank  is  filled  with  water  up  to 
the  point  where  it  begins  to  trickle  into  the  effluent  tank. 

As  an  insect  repellent  a  thin  film  of  some  form  of  petroleum  may 
be  poured  on  the  surface  of  the  liquid  in  each  barrel. 

Practical  working  of  the  apparatus. — When  the  privy  is  to  be  used, 
the  rod  is  pulled  up  so  that  the  antisplashing  board  rises  to  within 
about  1  inch  below  the  surface  of  the  water.  The  fecal  material 


Fig.  4. — Inside  view  of  L.  R.  S.  privy. 


falls  into  the  water,  but  this  board  prevents  splashing,  and  thus 
overcomes  one  of  the  greatest  objections  thus  far  raised  to  the  wet 
system.  After  use,  the  person  sinks  the  antisplashing  board  by 
pushing  down  the  rod.  and  the  fecal  matter  then  floats  free  into  the 
water. 

Although  some  of  the  fecal  matter  floats,  it  is  protected  both  from 
fly  breeding  and  fly  feeding  in  the  following  ways:  First,  by  the 

463 


SANITARY  PRIVY. 


19 


automatically  closing  lid ;  second,  by  the  water ;  third,  by  the 
film  of  oil;  and,  fourth,  by  having  the  apparatus  located  in  a 
screened  place,  which  should  be  done  for  additional  safety,  liic 
film  of  oil  also  prevents  the  breeding  of  mosquitoes  in  the  barrel. 
Accordingly,  so  far  as  the  privy  as  a  breeding  or  feeding  place 
of  flies  and  mosquitoes  is  concerned,  the  model  in  question  com¬ 
pletely  solves  the  problem. 

The  fecal  material  becomes 
fermented  in  the  water  and 
gradually  liquefies ;  as  the 
excreta  settle,  the  level  of 
the  liquid  is  raised  and  the 
excess  flows  into  the  effluent 
tank,  where  it  is  protected 
from  insects  by  the  cover 
and  by  a  film  of  oil.  This 
effluent  may  be  allowed  to 
collect  in  the  tank  until  it 
reaches  the  level  of  the  con¬ 
necting  pipe,  when  it  may  be 
safely  disposed  of  in  various 
ways  to  be  discussed  later. 

It  is  thus  seen  that  this 
device  appears  to  meet  the 
following  requirements : 

(1)  It  solves  the  fly  prob¬ 
lem  and  the  mosquito  prob¬ 
lem,  so  far  as  the  privy  is 
concerned. 

(2)  It  liquefies  fecal  ma¬ 

terial  and  reduces  its  vol¬ 
ume,  so  that  it  may  be  safely 
disposed  of  more  easily  and 
cheaply  than  the  night  soil 
from  other  types  of  privies.  Fig  5._Rear  view  of  l.  r.  s.  privy. 

(3)  It  reduces  odor. 

(4)  It  reduces  the  labor  of  cleaning  the  privy  and  makes  this 
work  less  disagreeable. 

(5)  It  is  of  simple  and  inexpensive  construction. 

This  device  has  been  in  constant  operation  in  one  of  the  work¬ 
rooms  on  the  main  floor  of  the  Hygienic  Laboratory  at  Washington 
for  8  months  and  has  been  found  entirely  satisfactory.  From 
July  12,  1910,  to  April  1.  1911,  namely,  202  days,  it  has  been  used 

738  times,  giving  an  average  of  2f  defecations,  (with  urination)  per 
463 


20 


SANITARY  PRIVY. 


day.  The  amount  of  overflow  (effluent)  from  the  liquefying  tank 
has  been  59  gallons.  The  liquefying  tank  itself  consists  of  an 
ordinary  water-tight  40-gallon  whisky  barrel,  and  it  has  not  been 
necessary  thus  far  either  to  add  water  or  to  empty  it. 

Tests  of  this  device  are  now  being  made  in  out-of-doors  privies  in 
order  to  determine  the  effect  upon  it  of  varying  conditions  of  tem¬ 
perature  and  humidity.  Tests  are  also  being  made  to  bring  out 
whatever  objectionable  features  may  arise  in  connection  with  its 
general  use  and  to  determine  the  simplest  methods  of  managing  the 
device  so  that  any  family  will  have  no  difficulty  in  keeping  it  in 
proper  working  order. 

The  handle  of  the  antisplasher  should  come  up  through  the  seat 

board  at  the  side  of  the  hole.  By  this  arrangement  the  antisplasher 

can  be  raised  entirelv  out  of  the  water  and  thus  used  to  sink  the 

«/ 

toilet  paper  and  fecal  matter  if  too  much  floats  on  the  surface. 

As  an  effluent  tank,  various  receptacles  can  be  utilized.  If  an  iron 
pot  is  used,  place  on  stones  or  provide  with  legs  so  that  a  space  is  left 
under  it  to  permit  the  building  of  a  fire  as  the  effluent  can  be  easily 
and  cheaply  disinfected  by  heat. 

As  a  liquefying  tank  one  may  use  either  a.  barrel  or  an  iron  tank, 
or  a  box,  or  a  brick  vault,  or  a  concrete  vault.  Whatever  is  used 
for  this  purpose  must  be  strictly  water-tight.  Iron  or  concrete  will 
cost  more  than  wood,  but  on  account  of  greater  durability  will  be 
more  economical  in  the  long  run. 

The  larger  the  family  the  larger  the  liquefying  tank  must  be.  A 
40-gallon  barrel,  such  as  a  whisky  or  oil  barrel,  seems  sufficient  for  a 
family  af  3  adults.  For  a  larger  family,  the  capacity  should  be  in¬ 
creased  by  using  two  or  more  barrels  or  one  larger  receptacle,  in  the 
proportion  of  about  40  gallons  capacity  to  every  3  to  4  adults  in  the 
family. 

One  advantage  the  device  possesses  is  that  with  very  little  expense 
it  can  be  put  in  the  outhouses  already  in  use;  in  fact,  it  can  be  placed 
in  any  of  the  outhouses  on  the  farm,  such  as  barn  or  woodshed,  and 
thus  save  the  expense  of  building  for  this  special  purpose.  Wher¬ 
ever  put,  it  is  very  important  to  have  it  in  a  place  screened  against 
flies. 

From  the  out-of-door  experiments  thus  far  it  can  be  readily  fore¬ 
seen  that  two  factors  come  into  consideration  which  have  not  been 
found  important  in  the  indoor  privy,  namely,  evaporation  and 
changes  of  temperature. 

In  cold  weather  the  fermentation  is  not  so  rapid  as  in  warm 
weather,  and  on  this  account  the  contents  of  the  liquefying  tank  may 
gradually  thicken. 

463 


SANITARY  PRIVY. 


21 


\ 

The  evaporation  out  of  doors  will  vary  greatly  with  the  wind, 
humidity,  and  temperature  in  different  regions,  and  the  greater  the 
evaporation  the  thicker  the  material  in  the  liquefying  tank  becomes. 

Should  such  thickening  occur,  the  odor  will  increase,  and  it  will  be 
necessary  to  add  water  to  the  liquefying  tank.  In  order  to  prevent 
such  thickening,  it  may  be  found  necessary  in  some  instances  to  add 
water  from  time  to  time.  Just  how  often  and  how  much  water  should 
be  added,  under  adverse  conditions,  has'  not  yet  been  determined, 
but,  so  far  as  can  be  foreseen  at  present,  probably  a  bucketfull  (about 
2  gallons)  added  once  a  week  will  be  sufficient  for  a  single  barrel  used 
by  a  family  of  3  or  4  adults. 

Experiments  have  conclusively  demonstrated  that  the  principle 
of  the  L.  R.  S.  privy  is  good.  The  details  regarding  the  addition 
of  water  must  be  determined  experimentally  in  different  localities. 
Any  intelligent  farmer  should  be  able  to  determine  this  point  for  his 
own  locality.1 

If  this  type  of  privy  is  managed  fairly  intelligently,  the  indica¬ 
tions  are  that  the  liquefying  tank  will  rarely  need  cleaning,  probably 
not  oftener  than  once  in  several  years.  When  cleaning  does  become 
necessary,  this  can  be  done  in  several  ways:  The  barrel  may  be 
taken  out,  and  its  contents  burned;  or  the  contents  may  be  pumped 
or;dipped  out,  and  burned;  or  a  considerable  amount  (several  bar¬ 
relfuls)  of  water  can  be  poured  gradually  into  the  liquefying  tank, 
and  the  sludge  thoroughly  stirred  until  it  runs  over  into  the  effluent 
tank. 

In  the  experimental  L.  R.  S.  privy  the  only  paper  used  has  been 
the  regular  toilet  paper.  This  has  liquefied  with  sufficient  prompt¬ 
ness.  If  heavier  paper  (such  as  newspaper)  were  used,  this 
would  break  up  more  slowly,  and  allowance  for  it  might  have  to 
be  made  by  increasing  the  capacity  of  the  tank.  It  is  well  to  bear 
in  mind  that  the  ink  on  newspaper  is  likely  to  irritate  the  skin. 
Corncobs  and  similar  objects  would  certainly  interfere  materially 
with  the  successful  working  of  any  apparatus  of  this  kind. 

DIRECTIONS  EOR  BUILDING  A  SANITARY  PRIVY. 

There  are  many  different  ways  that  a  privy  building  can  be  con¬ 
structed.  The  details  of  construction  are  here  appended  for  only 
one  of  the  many  different  styles. 

In  order  to  put  the  construction  of  a  sanitary  privy  for  the  home 
within  the  carpentering  abilities  of  boys,  a  practical  carpenter  has 
been  requested  to  construct  models  to  conform  to  the  general  ideas 
expressed  in  this  article  and  to  furnish  estimates  of  the  amount  of 

1  It  should  be  understood  that  the  L.  R.  S.  privy  is  described  simply  as  a  type,  and 
may  be  modified  to  suit  varying  conditions. 

463 


22 


SANITARY  PRIVY 


✓ 


463 


SANITARY  PRIVY 


23 


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lumber,  hardware,  and  wire  screening  required.  Drawings  of  these 
models  have  been  made  during  the  process  of  construction  (figs.  8, 
9)  and  in  completed  condition  (figs.  6,  7).  The  carpenter  was  re¬ 
quested  to  hold  constantly  in  mind  two  points,  namely,  (1)  economy 
and  (2)  simplicity  of  construction.  It  is  believed  that  any  14-year- 


Fig.  7. — Rear  and  side  view  of  a  single-seated  sanitary  privy 


old  school  boy  of  average  intelligence  and  mechanical  ingenuity 
can,  by  following  these  plans,  build  a  sanitary  privy  for  his  home 
at  an  expense  for  building  materials,  exclusive  of  receptacle,  of 
$5  to  $10,  according  to  locality.  It  is  further  believed  that  the 
plans  submitted  cover  the  essential  points  to  be  considered.  They 

463 


24 


SANITARY  PRIVY 


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463 


SANITARY  PRIVY. 


25 


can  be  elaborated  to  suit  the  individual  tastes  of  persons  who  prefer 
a  more  elegant  and  more  expensive  structure.  For  instance,  the 
roof  can  have  a  double  instead  of  a  single  slant,  and  can  be  shingled ; 
the  sides,  front,  and  back  can  be  clapboarded,  or  they  can  be  shin¬ 
gled.  Instead  of  one  seat  (figs.  6,  7),  there  may  be  two,  three,  four, 
five,  or  six  seats,  according  to  need. 

A  SINGLE-SEATED  PRIVY. 

Nearly  all  privies  for  the  home  have  seats  for  two  persons,  but  a 
single-seated  privy  can  be  made  more  economically. 

Framework. — The  lumber  required  for  the  framework  of  the  out¬ 
house  shown  in  figure  6  is  as  follows  (see  figs.  8,  9)  : 

A,  two  pieces,  6  by  6  inches,  4  feet  long. 

B,  one  piece,  4  by  4  inches,  3  feet  10  inches  long. 

C,  two  pieces,  4  by  4  inches,  3  feet  4  inches  long. 

D,  two  pieces,  2  by  4  inches,  7  feet  9  inches  long. 

E,  two  pieces,  2  by  4  inches,  6  feet  7  inches  long. 

F,  two  pieces,  2  by  4  inches,  6  feet  3  inches  long. 

G,  two  pieces,  2  by  4  inches,  5  feet  long. 

H,  one  piece,  2  by  4  inches,  3  feet  10  inches  long. 

I,  two  pieces,  2  by  4  inches,  3  feet  4  inches  long. 

J,  two  pieces,  2  by  4  inches,  3  inches  long. 

K,  two  pieces,  1  by  6  inches,  4  feet  7  inches  long.  The  ends  of  K  should  be 
trimmed  after  being  nailed  in  place. 

L,  two  pieces,  1  by  6  inches,  4  feet  long. 

First  lay  down  the  sills  marked  A,  and  join  them  with  the  joist 
marked  B;  then  nail  in  position  the  two  joists  marked  C,  with  their 
ends  3  inches  from  the  outer  edge  of  A;  raise  the  corner  posts  (D 
and  F),  spiking  them  at  bottom  to  A  and  C,  and  joining  them  with 
L,  I2,  G,  and  K;  raise  doorposts  E,  fastening  them  at  J,  and  then 
spike  Ii  in  position ;  H  is  fastened  to  K. 

Sides. — Each  side  (fig.  7)  requires  four  boards  (a)  12  inches  wide 
by  1  inch  thick  and  8  feet  6  inches  long;  these  are  nailed  to  K,  L, 
and  A.  The  corner  boards  must  be  notched  at  G,  allowing  them  to 
pass  to  bottom  of  roof;  next  draw  a  slant  from  front  to  back  at 
G-G  on  the  outside  of  the  boards,  and  saw  the  four  side  boards  to 
correspond  with  this  slant. 

Back. — The  back  (fig.  7)  requires  two  boards  (b)  12  inches  wide 
by  1  inch  thick  and  6  feet  11  inches  long,  and  two  boards  (<?)  12  inches 
wide  by  1  inch  thick  and  6  feet  5  inches  long.  The  two  longest 
boards  (b)  are  nailed  next  to  the  sides;  the  shorter  boards  (c)  are 
sawed  in  two,  so  that  one  piece  (c1)  measures  4  feet  6  inches,  the 
other  ( c 2)  1  foot  11  inches;  the  longer  portion  (c1)  is  nailed  in 
position  above  the  seat;  the  shorter  portion  ( c 2)  is  later  utilized  in 
making  the  back  trapdoor. 

463 


26 


SANITARY  PRIVY 


Floor. — The  floor  (fig.  6)  requires  four  boards  ( d )  which  (when 
cut  to  fit)  measure  1  inch  thick,  12  inches  wide,  and  3  feet  10  inches 
long. 


FIG<  9. — The  framework  (assembled)  for  a  single-seated  sanitary  privy.  (Stiles,  1010.) 


Front.— The  front  boards  may  next  be  nailed  on.  The  front  (fig. 
6)  requires  (besides  the  door)  two  boards  (<?),  which  (when  cut  to 
463 


SANITARY  PRIVY.  27 

fit)  measure  1  inch  thick,  9  inches  wide,  and  8  feet  5  inches  long; 
these  are  nailed  next  to  the  sides. 

Roof. — The  roof  (fig.  7)  may  now  be  finished.  This  requires  five 
boards  (/)  measuring  (when  cut  to  fit)  1  inch  thick,  12  inches  wide, 
and  6  feet  long.  They  are  so  placed  that  they  extend  8  inches  beyond 
the  front.  The  joints  (cracks)  are  to  be  broken  (covered)  by  laths 
J  inch  thick,  3  inches  broad,  and  6  feet  long. 

Box. — The  front  of  the  box  (fig.  6)  requires  two  boards,  1  inch 
thick  and  3  feet  10  inches  long.  One  of  these  ( g )  may  measure  12 
inches  wide,  and  the  other  (A)  5  inches  wide.  These  are  nailed  in 
place,  so  that  the  back  of  the  boards  is  18  inches  from  the  inside  of  the 
back  boards.  The  seat  of  the  box  requires  two  boards,  1  inch  thick, 
3  feet  10  inches  long;  one  of  these  (i)  may  measure  12  inches  wide, 
the  other  (})  7  inches  wide.  One  must  be  jogged  (cut  out)  to  fit 
around  the  back  corner  posts  (F).  An  oblong  hole,  10  inches  long 
and  7J  inches  wide,  is  cut  in  the  seat.  The  edge  should  be  smoothly 
rounded  or  beveled.  An  extra  (removable)  seat  for  children  may 
be  made  by  cutting  a  board  1  inch  thick,  15  inches  wide,  and  20  inches 
long;  in  this  seat  a  hole  is  cut,  measuring  7  inches  long  by  6  inches 
wide;  the  front  margin  of  this  hole  should  be  about  3  inches  from 
the  front  edge  of  the  board.  To  prevent  warping,  a  cross  cleat  is 
nailed  on  top  near  or  at  each  end  of  the  board. 

A  cover  (k)  to  the  seat  should  measure  1  inch  thick  by  15  inches 
wide  by  20  inches  long;  it  is  cleated  on  top  near  the  ends  to  prevent 
warping;  it  is  hinged  in  back  to  a  strip  1  inch  thick,  3  inches  wide, 
and  20  inches  long,  which  is  fastened  to  the  seat.  Cleats  (m)  may 
also  be  nailed  on  the  seat  at  the  sides  of  the  cover.  On  the  inside 
of  the  back  board,  12  inches  above  the  seat,  there  should  be  nailed  a 
block  (£),  2  inches  thick,  6  inches  long,  extending  forward  3J  inches; 
this  is  intended  to  prevent  the  cover  from  falling  backward  and  to 
make  it  fall  down  over  the  hole  when  the  occupant  arises. 

On  the  floor  of  the  box,  underneath  the  seat  (fig.  7),  two  or  three 
cleats  (n)  are  nailed  in  such  a  position  that  the  tub  will  always  be 
in  the  center;  the  position  of  these  cleats  depends  upon  the  size  of 
the  tub. 

Back  trapdoor. — In  making  the  back  of  the  privy  (fig.  7),  the  two 
center  boards  ( c )  were  sawed  at  the  height  of  the  bottom  of  the  seat. 
The  small  portions  (c2)  sawed  off  (23  inches  long)  are  cleated  ( o )  to¬ 
gether  so  as  to  form  a  back  trapdoor  which  is  hinged  above;  a  bolt 
or  a  button  is  arranged  to  keep  the  door  closed. 

Front  door. — The  front  door  (fig.  6)  is  made  by  cleating  ( p ) 
together  three  boards  (q)  1  inch  thick,  10  inches  wide,  and  (when 
finished)  0  feet  7  inches  long;  it  is  best  to  use  three  cross  cleats  (/?) 
(1  inch  thick,  0  inches  wide,  30  inches  long),  which  are  placed  on  the 

463 


28 


SANITARY  PRIVY. 


inside.  The  door  is  hung  with  two  hinges  (6-inch  “strap”  hinges 
will  do),  which  are  placed  on  the  right  as  one  faces  the  privy,  so  that 
the  door  opens  from  the  left.  The  door  should  close  with  a  coil 
spring  (cost  about  10  cents)  or  with  a  rope  and  weight,  and  may 
fasten  on  the  inside  with  a  catch  or  a  cord.  Under  the  door  a  cross¬ 
piece  (r)  1  inch  thick,  4  inches  wide,  30  inches  long  (when  finished) 
may  be  nailed  to  the  joist.  Stops  ( s )  may  be  placed  inside  the  door 
as  shown  in  figure  6.  These  should  be  1  inch  thick,  3  inches  wide, 
and  6  feet  6  inches  long,  and  should  be  jogged  (cut  out)  (t)  to  fit  the 
cross  cleats  (p)  on  the  door.  Close  over  the  top  of  the  door  place  a 
strip  1  inch  thick,  2  inches  wide,  30  inches  long,  nailed  to  I  (fig. 
9).  A  corresponding  piece  (v)  is  placed  higher  up  directly  under 
the  roof,  nailed  to  G.  A  strap  or  door  pull  is  fastened  to  the  outside 
of  the  door. 

Ventilators. — There  should  be  5  ventilators  (w).  One  is  placed  at 
each  side  of  the  box,  directly  under  the  seat ;  it  measures  6  to  8  inches 
square.  Another  (12  inches  square)  is  placed  near  the  top  on  each 
side  of  the  privy.  A  fifth  (30  inches  long,  8-J  inches  wide)  is  placed 
over  the  door,  between  G  and  Ix  (figs.  6,  9).  The  ventilators  are 
made  of  15-mesh  copper  wire,  which  is  first  tacked  in  place  and  then 
protected  at  the  edge  with  the  same  kind  of  lath  that  is  used  on  the 
cracks  and  joints. 

If  the  L.  R.  S.  system  (p.  17)  is  used  and  the  barrel  or  tank  brought 
close  to  the  seat,  the  ventilators  at  the  sides  of  the  box  may  be  done 
away  with,  and  the  barrel  may  be  ventilated  by  a  pipe  (such  as  a 
joint  of  stove  pipe),  extending  through  the  seat  to  the  roof  or  through 
the  back  of  the  house ;  this  ventilator  should  be  screened. 

Lath.. — Outside  cracks  (joints)  are  covered  with  lath  \  inch  thick 
by  3  inches  wide. 

Receptacle. — For  a  receptacle,  saw  a  water-tight  barrel  to  fit  snugly 
under  the  seat;  or  purchase  a  can  or  tub,  as  deep  (17  inches)  as  the 
distance  from  the  under  surface  of  the  seat  to  the  floor.  If  it  is  not 
possible  to  obtain  a  tub,  barrel,  or  can  of  the  desired  size,  the  recep¬ 
tacle  used  should  be  elevated  from  the  floor  by  blocks  or  boards  so 
that  it  fits  snugly  under  the  seat.  A  gahTanized  can  measuring  16 
inches  deep  and  16  inches  in  diameter  can  be  purchased  for  about  $1, 
or  even  less.  An  empty  candy  bucket  of  about  the  same  size  can  be 
purchased  for  about  10  cents. 

This  same  outhouse  may  be  used  for  the  L.  R.  S.  privy  (p.  17),  in 
which  case  it  is  not  necessary  to  extend  the  floor  under  the  seat ; 
instead  of  doing  this,  a  hole  is  dug  deep  enough  to  receive  the  barrel 
or  vault;  or  if  preferred,  the  house  can  be  elevated  high  enough  to 
make  room  for  the  barrel  (see  fig.  3). 

463 


SANITARY  PRIVY. 


29 


Order  for  material. — The  carpenter  lias  made  out  the  following 
order  for  lumber  (pine,  No.  1  grade)  and  hardware  to  be  used  in 
building  a  privy  such  as  is  shown  in  figure  6 : 

1  piece,  6  by  6  inches  by  8  feet  long,  24  square  feet. 

1  piece,  4  by  4  inches  by  12  feet  long,  16  square  feet. 

5  pieces,  2  by  4  inches  by  16  feet  long,  54  square  feet. 

3  pieces,  1  by  6  inches  by  16  feet  long,  24  square  feet. 

2  pieces,  1  by  9  inches  by  9  feet  long,  14  square  feet. 

3  pieces,  1  by  10  inches  by  7  feet  long,  18  square  feet. 

15  pieces,  1  by  12  inches  by  12  feet  long,  180  square  feet. 

12  pieces,  £  by  3  inches  by  16  feet  long,  48  square  feet. 

2  pounds  of  20-penny  spikes. 

6  pounds  of  10-penny  nails. 

2  pounds  of  6-penny  nails. 

7  feet  screen,  15-mesh,  copper,  12  inches  wide. 

4  hinges,  6-inch  “  strap,”  for  front  and  back  doors. 

2  hinges,  6-inch  T,  or  3-inch  “  butts,”  for  cover. 

1  coil  spring  for  front  door. 

According  to  th©  carpenter’s  estimate  these  materials  will  cost 
from  $5  to  $10,  according  to  locality. 

There  is  some  variation  in  the  size  of  lumber,  as  the  pieces  are  not 
absolutely  uniform.  The  sizes  given  in  the  lumber  order  represent 
the  standard  sizes  which  should  be  ordered,  but  the  purchaser  need 
not  expect  to  find  that  the  pieces  delivered  correspond  with  mathe¬ 
matical  exactness  to  the  sizes  called  for.  On  this  account  the  pieces 
must  be  measured  and  cut  to  measure  as  they  are  put  together. 

ESTIMATE  OF  MATERIAL  FOR  SCHOOL  OR  CHURCH  PRIVY. 

The  following  estimate  of  building  materials  has  been  made,  by 
a  carpenter,  for  the  construction  of  a  six-seated  school  or  church 
privy.  The  estimated  cost  of  these  materials  is  $25  to  $50,  accord¬ 
ing  to  locality ;  this  does  not  include  the  pails  or  barrels : 

3  pieces,  6  by  6  inches  by  20  feet,  180  square  feet. 

1  piece,  6  by  6  inches  by  8  feet,  24  square  feet. 

Scantling,  2  by  4  inches,  165  square  feet. 

Boards,  1  by  12  inches,  600  square  feet. 

Boards,  1  by  10  inches,  185  square  feet. 

Boards,  1  by  8  inches,  100  square  feet. 

Boards,  1  by  6  inches,  80  square  feet. 

Boards,  \  by  3  inches,  100  square  feet. 

Flooring,  80  square  feet. 

40  feet  15-mesh  copper  wire  screen,  12  inches  wide. 

12  pairs  of  hinges,  6-inch  “  strap.” 

6  pairs  of  hinges,  6-inch  T. 

3  pounds  of  20-penny  spikes; 

15  pounds  of  10-penny  nails. 

8  pounds  of  6-penny  nails. 

6  coil  springs  for  front  doors. 

6  knobs  or  latches. 

463 


30 


SANITARY  PRIVY. 


HOW  TO  KEEP  A  PRIVY  SANITARY. 

It  is  necessary  not  only  to  build  a  privy  properly  but  also  to  keep 
it  in  proper  condition.  This  involves  cleaning  out  and  disposing 
of  the  excreta  in  such  a  way  as  to  prevent  all  possibility  of  the  spread 
of  disease  germs  from  the  material.  The  disagreeable  labor  involved 
varies  according  to  the  kind  of  privy  in  use,  but  is  less  with  the 
L.  R.  S.  privy  than  with  the  other  types. 

Wrong  ways  of  disposing  of  night  soil. —  (1)  The  point  can  not  be 
emphasized  too  strongly  that  the  use  of  fresh  night  soil  as  fertilizer 
endangers  the  health  and  life  not  only  of  evenr  person  on  the  farm 
itself,  but  of  all  people  who  handle  or  who  consume  the  fresh  vege¬ 
tables  and  fresh  milk  from  such  a  farm.  The  custom  is  forbidden  by 
law  in  some  States. 

(2)  If  the  fresh  night  soil  is  simply  buried,  germs  of  disease  may 
later  be  brought  to  the  surface,  and  thus  infection  may  be  spread. 
Further,  the  popular  idea  that  all  the  fly  grubs  in  the  night  soil  are 
killed  by  burial  is  not  correct,  for  these  grubs  can  crawl  up  through 
ars  much  as  6  feet  of  sand,  reach  the  surface,  develop  into  flies,  and 
carry  filth  and  disease  germs  to  the  food.  Further,  also,  if  the  fresh 
night  soil  is  buried,  it  may  infect  the  water  supply  (springs,  wells, 
etc.),  and  thus  spread  disease.  Widespread  as  is  the  custom  of  bury¬ 
ing  fresh  excreta,  it  is  a  custom  which  in  the  light  of  present-day 
knowledge  must  be  viewed  as  being  far  from  safe,  although  when 
done  with  great  care  it  does  decrease  the  dangers  to  some  extent. 

(3)  Mixing  night  soil  with  manure  is  especially  dangerous,  and  feed¬ 
ing  it  to  chickens  and  hogs  is  both  filthy.and  dangerous. 

(4)  To  leave  the  night  soil  on  the  ground  near  the  privy  is  de¬ 
liberately  to  expose  the  family  and  neighbors  to  sickness. 

(5)  In  some  instances  farmers  collect  the  fresh  night  soil  from 
towns  and  villages,  and  haul  it  to  their  farms,  under  the  impression 
that  if  it  is  promptly  plowed  under  it  will  enrich  the  land  and  no 
harm  can  result.  Farmers  should  thoroughly  understand  that  the 
following  of  such  a  practice  is  attended  with  great  danger,  as  typhoid 
fever,  hookworm  disease,  and  other  infections  may  therebv  be  intro- 
duced  from  the  town  to  a  healthful  farm. 

(6)  In  some  instances,  the  privy  is  built  over  a  creek,  or  the  fresh 
excreta  are  thrown  into  a  stream  or  lake.  Such  practices  may  en¬ 
danger  the  lives  of  persons  living  downstream. 

The  right  way  to  dispose  of  night  soil. — Since  it  is  not  known,  at  any 
given  time,  which  members  of  a  community  harbor  disease  germs  in 
their  intestines,  the  invariable  rule  should  be  adopted  to  consider  all 
fresh  night  soil  as  a  virulent  poison  and  to  dispose  of  it  accordingly. 

The  only  safe  way  of  disposing  of  fresh  night  soil  from  the  style 
of  privy  shown  in  figures  (>  and  7  is  to  burn  it  or  disinfect  it  by  means 
463 


SANITARY  PRIVY. 


31 


of  heat.  Any  other  method,  such  as  burial  or  any  practicable  treat¬ 
ment  Avith  chemical  disinfectants  (lime,  etc.),  although  lessening  the 
danger  to  some  extent,  still  carries  AATith  it  risks  in\rolving  human  life. 

If  the  wet  method  (p.  16)  be  used  in  the  style  of  privy  shoAvn  in 
figures  6  and  7,  the  excreta  had  best  be  heated  to  212°  F.,  after  which 
the  material  may  safely  be  used  as  fertilizer.  A  second  method  is  to 
permit  the  filth  to  ferment  in  water  in  coArered  tubs  or  barrels  for  not 
less  than  a  week  after  removal  from  the  privy ;  then  pour  in  a  disin¬ 
fectant  (such  as  chloride  of  lime,  one-fourth  pound  to  the  gallon  of 
excreta)  ;  the  material  should  then  be  buried.  This  second  method 
greatly  reduces  but  does  not  entirely  remOA^e  the  danger  of  the  spread 
of  disease. 

E fluent  {overflow)  from  the  L.  R.  S.  privy. — From  what  has  been 
said  above,  it  is  clear  that  the  proper  disposal  of  night  soil  always 
involves  some  labor  and  trouble,  but  it  is  important  constantly  to 
hold  in  mind  the  truth  that  the  results  obtained,  in  better  health, 
smaller  doctors’  bills,  and  the  saving  of  human  life,  more  than  justify 
the  efforts  expended. 

The  L.  R.  S.  privy  reduces  the  volume  of  the  excreta  and  converts 
the  material  into  an  easily  manageable  fluid,  so  that  the  disposal  of 
night  soil  from  this  type  of  privy  is  much  simplified.  The  methods 
of  disposal  which  come  into  consideration  are  the  following : 

(1)  Heat:  If  a  suitable  (metallic)  vessel  is  provided  to  receive  the 
effluent,  a  fire  may  be  built  under  the  vessel  and  the  effluent  heated 
to  212°  F.  Or  if  a  wooden  or  concrete  effluent  tank  is  used,  the 
effluent  may  be  transferred  to  some  other  vessel  for  heating. 

After  such  treatment  the  fluid  may  be  safely  used  for  fertilizer 
under  any  conditions. 

Heat  disinfection  is  the  only  measure  which  can  to-day  be  recom¬ 
mended  unreservedly. 

(2)  Burial:  Burial  will  unquestionably  decrease  the  danger  of 
spreading  infection,  but  in  the  present  state  of  knoAvledge  this  method 
of  disposal  can  not  be  relied  upon  as  safe.  If  burial  of  the  effluent 
is  practiced,  the  fluid  should  be  disposed  of  not  less  than  300  feet 
from  and  doAvnhill  from  any  neighboring  Avater  supply  and  not  less 
than  2  feet  ufiderground,  and  then  only  provided  the  soil  itself  is  a 
good  filter.  Burial  in  a  limestone  region  may  contaminate  water 
supplies  miles  aAA^ay. 

(3)  Chemical  disinfection:  Chemical  disinfectants,  such  as  chlo¬ 
rinated  lime  and  certain  coal-tar  derivatives,  have  the  great  adA^antage 
of  cheapness  and  can  be  relied  upon  to  destroy  the  disease-causing 
bacteria  in  the  night  soil.  The  knowledge  regarding  the  action  of 
chemical  disinfectants  upon  the  eggs  and  spores  of  the  various  animal 
parasites  is  at  present  very  rudimentary,  but,  so  far  as  results  are 
known,  their  practicable  use  does  not  seem  to  be  so  efficient  in  the 

463 


32 


SANITARY  PRIVY. 


destruction  of  the  animal  parasites  as  of  the  bacteria.  Therefore, 
pending  further  investigations,  the  use  of  chemically  treated  excre¬ 
ment  as  fertilizer  should  not  be  regarded  as  unqualifiedly  safe. 

(4)  Chemical  disinfection,  with  subsequent  burial:  Inasmuch  as 
chemical  disinfection  can  be  relied  upon  to  destroy  the  disease-pro¬ 
ducing  bacteria  in  night  soil,*  and  inasmuch  as  burial  greatly  reduces 
the  danger  from  animal  parasites,  a  suitable  combination  of  the  two 
methods  (chemical  disinfection  and  burial)  can  be  used  with  reason¬ 
able  safety. 

(5)  Sewers:  In  partially  sewered  towns  the  effluent  from  these 
privies  may  be  emptied  into  the  sewers.  If  conditions  are  such  that 
the  addition  of  this  material  to  the  sewage  is  dangerous,  then  the 
entire  sewer  system  needs  correction. 

THE  PRIVY  AT  THE  COUNTRY  SCHOOL  AND  CHURCH. 

Although  a  farmer  may  prevent  soil  pollution  on  his  own  farm  by 
the  use  of  sanitary  privies,  his  children  may  be  exposed  to  the  dan¬ 
gers  of  soil  pollution  at  the  schools  which  they  attend,  and  his  entire 
family  may  be  so  exposed  even  when  they  attend  church,  unless  the 
schools  and  churches  are  provided  with  sanitary  privies.  In  fact, 
schools  and  churches  not  provided  with  such  outhouses  necessarily 
form  distributing  centers  from  which  certain  diseases  spread  to  clean 
farms. 

CIVIC  RESPONSIBILITY  IN  RESPECT  TO  PRIVIES. 

Lack  of  sanitary  privies  on  neighboring  farms  may  be  responsible 
for  cases  of  typhoid  fever,  hookworm  disease,  and  other  infections 
on  farms  which  are  provided  with  sanitary  privies,  because  disease 
germs  may  be  carried  for  considerable  distances  by  flies,  by  animals, 
by  feet  of  persons,  by  wagon  wheels,  or  by  drainage  from  one  farm 
to  another. 

In  view  of  these  well-established  facts  it  is  evident  that  among  the 
highest  duties  that  rest  upon  a  farmer,  as  a  father  and  citizen,  is  not 
only  to  have  a  sanitary  privy  on  his  farm,  but  to  insist  that  the 
pollution  of  soil  with  human  excreta  be  prevented  throughout  the 
entire  neighborhood  by  the  use  of  sanitary  privies. 

In  the  United  States  about  400,000  persons  suffer  from  and  about 
35,000  die  from  typhoid  each  year ;  over  2,000,000  persons  have  hook¬ 
worm  disease.  Thousands  of  these  deaths  and  many  thousands  oi 
these  cases  of  disease  might  be  prevented  b}^  the  simple  use  of  sani¬ 
tary  privies.  A  compulsory  sanitary  privy  law  or  ordinance  should 
therefore  be  enacted  and  be  strictly  enforced  in  every  locality  not 
provided  with  a  properly  maintained  sewer  system. 

463 


O 


